Rotary field-magnet for electrical machines.



No. 668,|94. Patontad Feb. I9, I91. B. G. LAMME.

ROTARY FIELD IAGNET FUR ELECTRICAL MACHINES.

' (Applluflon mod July 14, 1900.

(lo Ilodal.)

WITNESSES: 1,? I II/ VLZT 01?.

13 H 94% gg W M .ATTURNEY.

UNITED STATES PATENT OFFICE.

BENJAMIN G. LAMME, OF PITTSBURG, PENNSYLVANIA, ASSIGNOR TO THE WESTINGHOUSE ELECTRIC & MANUFACTURING COMPANY, OF

PENNSYLVANIA.

ROTARY FIELD-MAGNET FOR ELECTRICAL MACHINES.

SPECIFICATION forming part of Letters Patent No. 668,194, dated February 19, 1901.

Application filed July 14, 1900. Serial No- 23,652. No model.)

To all whmn it may concern:

Be it known that I, BENJAMIN G. LAMME,

'a citizen of the United States,residing at Pittsburg, in the county of Allegheny and State of Pennsylvania, have invented new and useful Improvements in Rotary Field-Magnets for Electrical Machines, of which the following is a specification.

My invention relates to electrical machines, and particularly to rotating field-magnets for machines employed for generating alternating currents.

The object of my invention is to provide a field-magnet which shall be adapted for rotation at high speeds and which shall be both simple and substantial in construction and in which the temperature will not rise beyond a safe limit. With these ends in view I have devised the means shown in the accompanying drawings, in which- Figure 1 is a View, partially in end elevation and partially in section, of a field-mag net core constructed in accordance with my invention. Fig. 2 is a central longitudinal section of the magnet-core shown in Fig. 1, the ends of the shaft on which the core is mounted being broken away.

The body portion of the core is built up of a plurality of sections, five of such sections being shown in the drawings and being designated by the numerals 1 to 5, inclusive. Each of these divisions or sections may be built up of thin laminae, if desired, as is usual in electrical machines, or they may be of solid construction, except as hereinafter stated, provided such construction is found to be susceptible of use without danger of undue heating. Each of the sections or divisions 1, 2,

3, 4c, and 5 is provided with a plurality of 8, so arranged that they will be in alinement in the several divisions, and thus provide airpassages extending through the core from end to end and communicating with the annular passages 7. Each of the polar projections 6 is also provided on each side with one or more grooves 9, so that air circulation may take place between each coil and the polar projection on which it is located.

The internal diameters of the sections or divisions of the core vary progressively from end to end, the diameter of the bore of section 1 being the greatest and that of the bore of section 5 being the least, and the shaft 10 has five corresponding diameters the lengths of which are a little less than the thicknesses of the corresponding divisions of the core, so that these divisions may be pressed onto the shaft and held firmly in engagement therewith and also in engagement with each other, as is clearly indicated in Fig. 2. Suitable feathers or splines 11 may also be employed, as indicated. 1

In order that the several divisions or sections of the core may be still further anchored in position and the coils also beheld securely in position on the polar projections against the action of centrifugal force, I provide a comparatively heavy bar or plate 12 for each alined set of polar projections, the outer portion of which is wider than said projections, and fasten the same in position to the ends of the polar projections by means of bolts 13, two of such bolts being shown in the drawings as employed for fastening the end piece 12 to each of the core-divisions.

The construction shown and described was designed for operation directly by a steam turbine that operates at extremely high speeds and is peculiarly adapted for this purpose; but it may be used in other relations, and is therefore not limited to operation by anyspecific type of engine.

I claim as my invention- 1. A rotary field-magnet for electrical machines having its body portion built up of a plurality of sections the meeting faces of which are transverse to the axis and having pole-piece end blocks or plates each of which extends from end to end of the body portion and is bolted to the several body-sections.

2. A rotary field-magnet for electrical machines having its body portion built up of a plurality of sections the meeting faces of which are transverse to the axis and having pole-piece end blocks or plates each of which projects beyond both the ends and sides of the body of the corresponding pole-piece and is bolted to each of the body-sections.

3. A rotary field-magnet for electrical inachines having its body portion built up of a plurality of sections the contiguous faces of which are perpendicular to the axis and separated by air-spaces and having pole-piece ends severally extending from end to end of the body portion and bolted to the several sections thereof.

4;. A rotary field-magnet for electrical machines having a body portion built up of annular sections of different internal diameter, a shaft having as many successive lengths of different diameter as there are sections in the body portion, and a plurality of pole-piece ends severally bolted to the respective sections of the body portion.

5. In a rotary field-magnet for electrical machines, a shaft having aplurality of successive divisions of gradually-decreasing diameter, a plurality of annular core-plates of slightly greater thickness than the lengths of the shaft-divisions and having internal diameters corresponding to the diameters of said divisions and pole-piece ends bolted to the several core-plates.

6. A rotary field-magnet for electrical machines comprising a plurality of core-plates having alining perforations and separated by annular spaces with which said alining perforations communicate and solid pole-piece ends severally bolted to pole-piece projections on the core-plates.

7. A rotary field-magnet for electrical machines comprising a shaft, a plurality of coreplates wedged thereon and a plurality of polepiece ends each of which is bolted to all of the core-plates,said core-plates being separated by annular air-spaces and provided with alined openings at right angles to said spaces.

8. A rotary field-magnet for electrical machines comprising a body portion built up of core-plates having corresponding polar projections and pole-piece end plates each ofwhich is bolted to all of the polar projections corresponding to one pole, said core-plates being separated by annular spaces and provided with alined openings that communicate with said spaces and the polar projections being provided with side grooves that communicate with said spaces.

In testimony whereof I have hereunto subscribed my name this 9th day of July, 1900. BENJ. G. LAMME.

Witnesses:

WEsLEY G. CARR, BIRNEY HINEs. 

